Effect of Glomus mosseae and Piriformospora indica and different levels of organic matter on the relationships between related characters with wheat yield

To study the response of yield and yield components of wheat to mycorrhiza and mycorrhiza-like fungi at different levels of organic matters and to determine the relationship between the effective characteristics on yield, a pot experiment was conducted in 2010, at Dryland Agricultural Research Institute using randomized completely design with four replications. Treatments were considered organic matter from spent mushroom compost at three levels (0, 25 and 50 Mg ha-1) and fungi symbiosis in four levels [non-inoculation mycorrhiza (Glomus mosseae), mycorrhiza-like (Piriformospora indica) and co-inoculation of two fungi]. The measured characteristics included plant yield, yield components and characteristics such as peduncle length, extrusion length, plant height and spike length. Results indicated that compost had a positive and significant effect in all studied characteristics except 1000-grain weight. Although P. indica in low levels and Glomus mosseae in moderate and high levels of organic matter produced more grain and biological yield, overall, coinoculation of two fungi showed the best performance. Stepwise regression and path analysis were conducted separately for each levels of organic matter. The results indicated that grain number per plant and 1000-grain weight in the without compost treatment, biologic yield, harvest index and spikelet fertility percentage in the 25 Mg ha-1 of compost and biologic yield and harvest index in the 50 Mg ha-1 of compost were entered in the final model. In general, grain number per plant in without compost and biological yield in 25 and 50 Mg ha-1 of compost had the most direct effect on grain yield.